Dictionary.com
Thesaurus.com

username

American  
[yoo-zer-neym] / ˈyu zərˌneɪm /

noun

Computers.
  1. Also called sign-in name,.  Also called login name,.  Also called sign-on name.  Also called logon name,.  a unique sequence of characters used to identify a user and allow access to a computer system, computer network, or online account.

  2. the part of an email address before the @ sign.


username British  
/ ˈjuːzəˌneɪm /

noun

  1. computing a name that someone uses for identification purposes when logging onto a computer, using chatrooms, or as part of his or her e-mail address

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of username

First recorded in 1970–75; user 1 ( def. ) + name ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Ilyas Lebleu, an A.I. research student based in France who edits Wikipedia under the username Chaotic Enby, first wrote the proposal that was debated and adopted as the site’s A.I. ban.

From Slate • Apr. 1, 2026

Law enforcement quickly identified Pysher as the person behind the username on Discord and tracked him to the motel, according to the complaint.

From Los Angeles Times • Feb. 23, 2026

She can be reached on Signal at the username tparti.37.

From The Wall Street Journal • Feb. 13, 2026

“It’s rare we get a non-temp market with so much attention and liquidity like this,” says a 31-year-old New York-based Kalshi trader whose username is NelsonOrAri.

From Barron's • Jan. 26, 2026

He went to the computer but realized it needed a log-on username and password.

From "City Spies" by James Ponti